PR tree-optimization/43833
[official-gcc/alias-decl.git] / gcc / emutls.c
blobb7ee3bdfa7cec09b1f43aba5bed1132e71cea4ee
1 /* TLS emulation.
2 Copyright (C) 2006, 2008, 2009 Free Software Foundation, Inc.
3 Contributed by Jakub Jelinek <jakub@redhat.com>.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 Under Section 7 of GPL version 3, you are granted additional
18 permissions described in the GCC Runtime Library Exception, version
19 3.1, as published by the Free Software Foundation.
21 You should have received a copy of the GNU General Public License and
22 a copy of the GCC Runtime Library Exception along with this program;
23 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
24 <http://www.gnu.org/licenses/>. */
26 #include "tconfig.h"
27 #include "tsystem.h"
28 #include "coretypes.h"
29 #include "tm.h"
30 #include "gthr.h"
32 typedef unsigned int word __attribute__((mode(word)));
33 typedef unsigned int pointer __attribute__((mode(pointer)));
35 struct __emutls_object
37 word size;
38 word align;
39 union {
40 pointer offset;
41 void *ptr;
42 } loc;
43 void *templ;
46 struct __emutls_array
48 pointer size;
49 void **data[];
52 void *__emutls_get_address (struct __emutls_object *);
53 void __emutls_register_common (struct __emutls_object *, word, word, void *);
55 #ifdef __GTHREADS
56 #ifdef __GTHREAD_MUTEX_INIT
57 static __gthread_mutex_t emutls_mutex = __GTHREAD_MUTEX_INIT;
58 #else
59 static __gthread_mutex_t emutls_mutex;
60 #endif
61 static __gthread_key_t emutls_key;
62 static pointer emutls_size;
64 static void
65 emutls_destroy (void *ptr)
67 struct __emutls_array *arr = ptr;
68 pointer size = arr->size;
69 pointer i;
71 for (i = 0; i < size; ++i)
73 if (arr->data[i])
74 free (arr->data[i][-1]);
77 free (ptr);
80 static void
81 emutls_init (void)
83 #ifndef __GTHREAD_MUTEX_INIT
84 __GTHREAD_MUTEX_INIT_FUNCTION (&emutls_mutex);
85 #endif
86 if (__gthread_key_create (&emutls_key, emutls_destroy) != 0)
87 abort ();
89 #endif
91 static void *
92 emutls_alloc (struct __emutls_object *obj)
94 void *ptr;
95 void *ret;
97 /* We could use here posix_memalign if available and adjust
98 emutls_destroy accordingly. */
99 if (obj->align <= sizeof (void *))
101 ptr = malloc (obj->size + sizeof (void *));
102 if (ptr == NULL)
103 abort ();
104 ((void **) ptr)[0] = ptr;
105 ret = ptr + sizeof (void *);
107 else
109 ptr = malloc (obj->size + sizeof (void *) + obj->align - 1);
110 if (ptr == NULL)
111 abort ();
112 ret = (void *) (((pointer) (ptr + sizeof (void *) + obj->align - 1))
113 & ~(pointer)(obj->align - 1));
114 ((void **) ret)[-1] = ptr;
117 if (obj->templ)
118 memcpy (ret, obj->templ, obj->size);
119 else
120 memset (ret, 0, obj->size);
122 return ret;
125 void *
126 __emutls_get_address (struct __emutls_object *obj)
128 if (! __gthread_active_p ())
130 if (__builtin_expect (obj->loc.ptr == NULL, 0))
131 obj->loc.ptr = emutls_alloc (obj);
132 return obj->loc.ptr;
135 #ifndef __GTHREADS
136 abort ();
137 #else
138 pointer offset = obj->loc.offset;
140 if (__builtin_expect (offset == 0, 0))
142 static __gthread_once_t once = __GTHREAD_ONCE_INIT;
143 __gthread_once (&once, emutls_init);
144 __gthread_mutex_lock (&emutls_mutex);
145 offset = obj->loc.offset;
146 if (offset == 0)
148 offset = ++emutls_size;
149 obj->loc.offset = offset;
151 __gthread_mutex_unlock (&emutls_mutex);
154 struct __emutls_array *arr = __gthread_getspecific (emutls_key);
155 if (__builtin_expect (arr == NULL, 0))
157 pointer size = offset + 32;
158 arr = calloc (size + 1, sizeof (void *));
159 if (arr == NULL)
160 abort ();
161 arr->size = size;
162 __gthread_setspecific (emutls_key, (void *) arr);
164 else if (__builtin_expect (offset > arr->size, 0))
166 pointer orig_size = arr->size;
167 pointer size = orig_size * 2;
168 if (offset > size)
169 size = offset + 32;
170 arr = realloc (arr, (size + 1) * sizeof (void *));
171 if (arr == NULL)
172 abort ();
173 arr->size = size;
174 memset (arr->data + orig_size, 0,
175 (size - orig_size) * sizeof (void *));
176 __gthread_setspecific (emutls_key, (void *) arr);
179 void *ret = arr->data[offset - 1];
180 if (__builtin_expect (ret == NULL, 0))
182 ret = emutls_alloc (obj);
183 arr->data[offset - 1] = ret;
185 return ret;
186 #endif
189 void
190 __emutls_register_common (struct __emutls_object *obj,
191 word size, word align, void *templ)
193 if (obj->size < size)
195 obj->size = size;
196 obj->templ = NULL;
198 if (obj->align < align)
199 obj->align = align;
200 if (templ && size == obj->size)
201 obj->templ = templ;